【作者】 靳硕学； 郭立平； 杨铮； 黎明； 周霖； 彭国良； 刘传胜； 巨新； 刘实；

【Author】 JIN Shuoxue1, GUO Liping1, YANG Zheng1, Li Ming1, ZHOU Lin1, PENG Guoliang1, LIU Chuansheng1, JU Xin2, LIU Shi3 1(Accelerator Laboratory, School of Physics, Wuhan University, Wuhan 430072, China) 2(School of Applied Science, University of Science and Technology Beijing, Beijing 100083, China) 3(Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China)

【机构】 武汉大学物理科学与技术学院加速器实验室； 北京科技大学应用科学学院； 中国科学院金属研究所；

【摘要】 材料中氦和氢的积累可引起材料性能的恶化甚至失效。为研究材料内氦和氢的存在形式、氦与氢及缺陷的相互作用、气泡的形成和演变过程以及各种因素的影响,我们建立了一套离子束能量最高为20keV的潘宁型气体离子源和引出聚焦系统,用于与200kV透射电镜联机,以便在离子注入现场原位观察氦和氢不同注入浓度下材料内部的微观结构及其变化过程。对离子源进行了氦离子的起弧、引出和聚焦测试。离子源可在15mA～60mA的放电电流范围内稳定地工作。在5×10-3Pa和1.5×10-2Pa工作气压下,放电电压约为380V和320V。低气压下引出的离子束流比高气压下大,且引出束流随着放电电流和吸极电压的增加而增加。等径三圆筒透镜可产生显著的聚焦作用,在距离透镜出口150cm处,离子束流密度可提高一个量级以上。对能量在10keV左右的氦离子获得了束流密度约200nA·cm-2的离子束,可以满足多种材料进行在线离子注入和原位电镜观测的需要。更多还原

【Abstract】 Accumulation of helium and/or hydrogen in nuclear materials may lead to the deterioration of performance. In order to provide a unique tool to investigate related basic issues such as the existance of helim and/or hydrogen inside the materials, interaction of helium with hydrogen and defects, formation of gas bubbles and its evolution as well as the effect of various factors, we have designed a cold cathode Penning ion source with maximum ion energy of 20keV, to be used to interfaced to a 200kV transimission electron microscope (TEM), to make it possible to contineously monitor the evolution of microstructue during the implation of helium and/or hydrogen. Performance of discharge voltage-current characteristics of the ion source, and extraction and focusing of the ion beam was performed. The ion source can operate steadily when the discharge current was in the range of 15～60mA. Under the gas pressure of 5×10-3 Pa and 1.5×10-2 Pa, the discharge voltage ia about 380V and 320 V, respectively. The extracted ion current under lower gas pressure is greater than that under higher gas pressure, and it increases with the increase of discharge current and extraction valtage. The ion lens consisting of three equal-diameter metal cylinder can focus the ion beam enormously, so that the beam density at the distance of 150cm away from the exit of the cylinder of the lens can increased above an order of magnitude. For the ion beam with energy of around 10keV, the measured beam density is about 200nA·cm-2, which may be applicable for ion implantation and in situ TEM observation for many kinds of nuclear materials.更多还原